U.S. patent application number 14/020916 was filed with the patent office on 2014-01-09 for grease gun.
This patent application is currently assigned to Milwaukee Electric Tool Corporation. The applicant listed for this patent is Milwaukee Electric Tool Corporation. Invention is credited to Scott D. Eisenhardt, Matthew J. Mergener, Troy C. Thorson.
Application Number | 20140008383 14/020916 |
Document ID | / |
Family ID | 46727113 |
Filed Date | 2014-01-09 |
United States Patent
Application |
20140008383 |
Kind Code |
A1 |
Mergener; Matthew J. ; et
al. |
January 9, 2014 |
GREASE GUN
Abstract
A grease gun includes a housing, a motor positioned within the
housing, a pump assembly coupled to and driven by the motor, and a
chamber supported by the housing in fluid communication with the
pump assembly. The chamber is configured to store a liquid. The
grease gun also includes an outlet in fluid communication with the
chamber and a measurement system operable to measure an amount of
liquid being dispensed through the outlet. The measurement system
monitors a change in current of the motor over a cycle of the pump
assembly, compares the change in current to a predetermined value,
and, if the change in current is greater than the predetermined
value, increases a pump cycle counter to indicate that liquid was
dispensed.
Inventors: |
Mergener; Matthew J.;
(Germantown, WI) ; Eisenhardt; Scott D.;
(Pewaukee, WI) ; Thorson; Troy C.; (Cedarburg,
WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Milwaukee Electric Tool Corporation |
Brookfield |
WI |
US |
|
|
Assignee: |
Milwaukee Electric Tool
Corporation
Brookfield
WI
|
Family ID: |
46727113 |
Appl. No.: |
14/020916 |
Filed: |
September 9, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13572085 |
Aug 10, 2012 |
8528782 |
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14020916 |
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61521903 |
Aug 10, 2011 |
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61521987 |
Aug 10, 2011 |
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61612835 |
Mar 19, 2012 |
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61612846 |
Mar 19, 2012 |
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61613888 |
Mar 21, 2012 |
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Current U.S.
Class: |
222/1 ; 222/333;
222/37; 222/63 |
Current CPC
Class: |
F16N 3/12 20130101; F16N
11/04 20130101; F16N 5/00 20130101; H01H 9/06 20130101; H01H 3/20
20130101; F16N 29/04 20130101 |
Class at
Publication: |
222/1 ; 222/37;
222/333; 222/63 |
International
Class: |
F16N 3/12 20060101
F16N003/12 |
Claims
1. A grease gun comprising: a housing; a motor positioned within
the housing; a pump assembly coupled to and driven by the motor; a
first actuator supported by the housing and electrically coupled to
the motor, the first actuator being actuatable to energize the
motor; a chamber supported by the housing and in fluid
communication with the pump assembly, the chamber being configured
to store a liquid; an outlet in fluid communication with the
chamber; and a measurement system electrically coupled to the motor
and including a second actuator, the second actuator being
actuatable to input a number of pump strokes to be performed, the
measurement system being operable to increase a pump cycle counter
each time the pump assembly performs a pump stroke and dispenses
liquid, and to automatically stop the motor when the pump cycle
counter equals the inputted number of pump strokes to be
performed.
2. The grease gun of claim 1, wherein the measurement system is
configured to automatically stop the motor while the first trigger
is actuated.
3. The grease gun of claim 1, wherein the second actuator includes
a dial, the dial being rotatable to input the number of pump
strokes to be performed.
4. The grease gun of claim 3, wherein at least a portion of the
dial extends outwardly through an opening in the housing.
5. The grease gun of claim 3, wherein the dial includes a plurality
of values on an outer surface of the dial, each value corresponding
to a different number of pump strokes to be performed.
6. The grease gun of claim 1, wherein the first actuator includes a
trigger.
7. The grease gun of claim 1, wherein the measurement system is
operable to monitor a change in current of the motor over a cycle
of the pump assembly, to compare the change in current to a
predetermined value, and, if the change in current is greater than
the predetermined value, to increase the pump cycle counter to
indicate that liquid was dispensed.
8. The grease gun of claim 7, wherein the measurement system is
operable to not increase the pump cycle counter if the change in
current is less than a predetermined value.
9. The grease gun of claim 7, wherein the predetermined value is
approximately 0.5 amps.
10. The grease gun of claim 1, wherein the chamber includes a
barrel assembly configured to receive a lubricant cartridge.
11. The grease gun of claim 1, further comprising an output hose
coupled to the housing and in fluid communication with the chamber,
the output house including the outlet.
12. A method of operating a grease gun, the grease gun including a
motor, a pump assembly coupled to the motor, an actuator
electrically coupled to the motor, a chamber in fluid communication
with the pump assembly and configured to store a liquid, an outlet
in fluid communication with the chamber, and a measurement system
electrically coupled to the motor, the method comprising: inputting
a number of pump strokes to be performed into the measurement
system; actuating the actuator to energize the motor; driving the
pump assembly with the motor while the actuator is actuated;
increasing a pump cycle counter of the measurement system each time
the pump assembly performs a pump stroke and dispenses liquid; and
automatically stopping the motor when the pump cycle counter equals
the inputted number of pump strokes to be performed.
13. The method of claim 12, wherein automatically stopping the
motor includes automatically stopping the motor while the actuator
is actuated.
14. The method of claim 12, wherein the actuator is a first
actuator, wherein the measurement system includes a second
actuator, and wherein inputting the number of pump strokes to be
performed includes actuating the second actuator to input the
number of pump strokes to be performed.
15. The method of claim 14, wherein the second actuator includes a
dial, and wherein actuating the second actuator includes rotating
the dial to input the number of pump strokes to be performed.
16. The method of claim 12, wherein the actuator includes a
trigger, and wherein actuating the actuator includes depressing the
trigger to energize the motor.
17. The method of claim 12, further comprising monitoring a change
in current of the motor over a cycle of the pump assembly,
comparing the change in current of the motor to a predetermined
value, and, if the change in current is greater than the
predetermined value, increasing the pump cycle counter to indicate
that liquid was dispensed.
18. The method of claim 17, further comprising holding the pump
cycle counter constant if the change in current is less than the
predetermined value.
19. The method of claim 17, wherein the predetermined value is
approximately 0.5 amps.
20. The method of claim 12, wherein inputting the number of pump
strokes to be performed includes inputting one of a volume of fluid
to be dispensed and a weight of fluid to be dispensed, and wherein
the method further comprises converting the one of the volume of
fluid to be dispensed and the weight of fluid to be dispensed to
the number of pump strokes to be performed.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 13/572,085, filed Aug. 10, 2012, which claims
priority to U.S. Provisional Patent Application No. 61/521,903,
filed Aug. 10, 2011, to U.S. Provisional Patent Application No.
61/521,987, filed Aug. 10, 2011, to U.S. Provisional Patent
Application No. 61/612,835, filed Mar. 19, 2012, to U.S.
Provisional Patent Application No. 61/612,846, filed Mar. 19, 2012,
and to U.S. Provisional Patent Application No. 61/613,888, filed
Mar. 21, 2012, the entire contents of all of which are hereby
incorporated by reference.
[0002] This application is related to U.S. patent application Ser.
No. 13/571,816, filed Aug. 10, 2012, by Troy C. Thorson et al., and
titled "GREASE GUN," the entire contents of which is also hereby
incorporated by reference.
FIELD
[0003] The present invention relates to grease guns and, more
particularly, to grease guns including lubricant measurement
systems.
BACKGROUND
[0004] Grease guns are commonly used in workshops, industry, and
garages to apply lubricant (e.g., grease) to specific points on a
piece of machinery. Grease guns typically include a coupler
positioned on the end of a hose that can be fitted to grease
fittings or zerks, which in turn provide fluid access to specific
joints, gears, and other important parts of a machine. The grease
gun then pumps lubricant into these points by way of a manual or
powered pump.
SUMMARY
[0005] In one independent embodiment, the invention may generally
provide a grease gun including a housing, a motor positioned within
the housing, a pump assembly coupled to and driven by the motor,
and a chamber supported by the housing in fluid communication with
the pump assembly. The chamber is configured to store a liquid. The
grease gun may also include an outlet in fluid communication with
the chamber and a measurement system operable to measure an amount
of liquid being dispensed through the outlet. The measurement
system may monitor a change in current of the motor over a cycle of
the pump assembly, compare the change in current to a predetermined
value, and, if the change in current is greater than the
predetermined value, increase a pump cycle counter to indicate that
liquid was dispensed.
[0006] In another independent embodiment, the invention may
generally provide a method of operating a grease gun. The grease
gun may include a motor, a pump assembly coupled to the motor, a
chamber in fluid communication with the pump assembly and
configured to store a liquid, and an outlet in fluid communication
with the chamber. The method may include driving the pump assembly
with the motor to dispense liquid from the chamber through the
outlet, monitoring a change in current of the motor over a cycle of
the pump assembly, comparing the change in current of the motor to
a predetermined value, and increasing a pump cycle counter, if the
change in current is greater than the predetermined value, to
indicate that liquid was dispensed.
[0007] Other independent aspects of the invention will become
apparent by consideration of the detailed description, claims and
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a grease gun embodying
aspects of the invention.
[0009] FIG. 2 is an enlarged view of a control panel on the grease
gun shown in FIG. 1.
[0010] FIG. 3 is a flowchart depicting operation of a lubricant
measurement system of the grease gun.
[0011] FIG. 4 is a perspective view of another grease gun embodying
aspects of the invention.
[0012] FIG. 5 is a perspective view of a portion of the grease gun
shown in FIG. 4 with a housing portion removed.
[0013] FIG. 6 is an enlarged view of another portion of the grease
gun shown in FIG. 4.
[0014] FIG. 7 is a cross-sectional view of the portion of the
grease gun shown in FIG. 6.
DETAILED DESCRIPTION
[0015] Before any independent embodiments of the invention are
explained in detail, it is to be understood that the invention is
not limited in its application to the details of construction and
the arrangement of components set forth in the following
description or illustrated in the following drawings. The invention
is capable of other independent embodiments and of being practiced
or of being carried out in various ways.
[0016] FIG. 1 illustrates an electrically-powered grease gun 10.
The illustrated grease gun 10 includes a housing 14, a motor 18
supported by and positioned within the housing 14, a pump assembly
22 coupled to and driven by the motor 18, a chamber 26 supported by
the housing 14 in fluid communication with the pump assembly 22,
and an output hose 30 in fluid communication with the chamber 26.
In the illustrated embodiment, the chamber 26 is a barrel assembly
that is configured to receive a lubricant cartridge. In other
embodiments, the chamber 26 may be configured to directly receive
and store a liquid, rather than a cartridge containing a liquid. In
addition, the illustrated output hose 30 is a flexible hose that
includes an outlet and is operable to dispense lubricant (or other
liquids) from the chamber 26. In other embodiments, the output hose
30 may be a rigid hose having an outlet, or the output hose 30 may
be omitted such that the outlet is directly formed on the housing
14 to dispense lubricant.
[0017] The illustrated motor 18 is powered by a power tool battery
pack such as, for example, an 18V Li-ion battery pack. In other
embodiments, the motor 18 may be powered by a battery pack having a
different voltage and/or chemistry, or the grease gun 10 may be a
corded power tool that is powered by an AC power source. In
operation, the motor 18 drives the pump assembly 22 to pump
lubricant from a lubricant cartridge positioned within the barrel
assembly 26. The lubricant is pumped through the output hose 30 and
dispensed from the grease gun 10 through a fitting, or other
outlet, on the end of the hose 30.
[0018] FIG. 2 illustrates a control panel 34 mounted on the grease
gun 10. The illustrated control panel 34 is a separate unit that is
permanently or removably coupled to the housing 14 of the grease
gun 10. In other embodiments, the control panel 34 may be
integrated into the housing 14 such that the entire grease gun
assembly is a single unit.
[0019] The control panel 34 controls a lubricant measurement system
of the grease gun 10, which may include a processor and a memory.
In the illustrated embodiment, the lubricant measurement system
monitors motor current during a pump cycle of the pump assembly 22
to determine the amount of lubricant (e.g., grease) being pumped
and dispensed from the grease gun 10 through the output hose 30. In
particular, the lubricant measurement system monitors the current
being drawn by the motor 18 to determine the number of pump strokes
performed by the pump assembly 22 that actually pump lubricant. In
some embodiments, the number of pump strokes may then converted
into a volume or weight of lubricant being dispensed by the gun 10.
The lubricant measurement system can also count the number of
strokes at both a high operating speed and a low operating speed of
the motor 18. In other embodiments, the lubricant measurement
system may count the number of pump strokes directly to determine
the amount of lubricant being dispensed.
[0020] In the illustrated embodiment, the control panel 34 includes
an LCD screen 38 and four manually operable actuators, or buttons,
42, 46, 50, 54. In other embodiments, the control panel 34 may
include different types of display screens or actuators such as,
for example, an LED screen and/or dials or switches. The
illustrated screen 38 alternately displays a "Run" page and a
"Stop" page. The "Run" page shows the amount of lubricant that has
already been pumped and dispensed by the grease gun 10. The "Stop"
page allows a user to set the amount of lubricant to be pumped and
dispensed by the gun 10. Actuating (e.g., depressing) the first
button 42 switches between these pages. Actuating the second and
third buttons 46, 50 adjusts the values on each page. Actuating the
fourth button changes the units displayed on the screen 38. For
example, the screen 38 can display the amount of lubricant already
pumped or to be pumped in ounces, grams, or number of pump strokes.
In such embodiments, the control panel 34 automatically converts
the number of pump strokes counted or to be counted by the
lubricant measurement system into a volume or weight of lubricant
already dispensed or to be dispensed. In other embodiments, the
screen 38 may display the amount of lubricant already pumped or to
be pumped in other units. In some embodiments, the control panel 34
may display maximum values of 15.88 ounces, 450.0 grams, or 794
pump strokes. Additionally or alternatively, the control panel 34
may also include a reset button to reset (e.g., zero) the volume,
weight, and/or number of pump strokes currently displayed on the
screen 38.
[0021] FIG. 3 is a flowchart 100 depicting operation of the
lubricant measurement system of the grease gun 10. When the grease
gun 10 is operated (e.g., when a trigger or other suitable actuator
is actuated to energize the motor 18 and drive the pump assembly
22), the processor and the memory of the lubricant measurement
system continuously collect and store operating characteristics
(e.g., current draw) of the motor 18. As operation of the grease
gun 10 proceeds, a Hall sensor, or other suitable sensor, of the
lubricant measurement system is triggered by a magnet at step 104.
The Hall sensor is positioned in the housing 14 (FIG. 1) and
coupled to the pump assembly 22 to monitor movement (e.g., pump
strokes) of the pump assembly 22. The Hall sensor is also
electrically coupled in communication with the processor of the
lubricant measurement system. Triggering the Hall sensor indicates
that one pump cycle is completed. The processor correlates the
stored current draw of the motor 18 over this time period (e.g.,
the time since the Hall sensor was last triggered) with the pump
cycle identified by the Hall sensor.
[0022] At step 108, the lubricant measurement system checks if the
change in current of the motor 18 (e.g., Imax of the motor 18 minus
Imin of the motor 18) over the pump cycle is greater than a
predetermined value. In the illustrated embodiment, the lubricant
measurement system checks if the change in current is greater than
approximately 0.5 amps. This predetermined value indicates whether
the grease gun 10 actually pumped lubricant during the measured
pump cycle. Changes in current that are smaller than 0.5 amps may
occur when, for example, an air bubble is in the pump assembly 22
or the lubricant cartridge in the barrel assembly 26 is empty. In
other embodiments, the predetermined value may be set at a larger
or smaller value than 0.5 amps, depending on the configuration of
the grease gun 10 and the type of components (e.g., motor, pump
assembly, lubricant, etc.) being used.
[0023] If the change in current is greater than the predetermined
value, the lubricant measurement system increases a pump cycle
counter by 1 at step 112. If the change in current is not greater
than the predetermined value, the lubricant measurement system does
not increase the pump cycle counter such that the pump cycle
counter is held or maintained at its previous value. After either
scenario, the lubricant measurement system continues to monitor the
motor current at step 116 until the Hall sensor is triggered again
at step 104. By not increasing the pump cycle counter when the
change in current is less than the predetermined value, the
lubricant measurement system compensates for pump strokes that do
not actually pump and dispense lubricant from the grease gun
10.
[0024] After the pump cycle counter is increased, the lubricant
measurement system compares the pump cycle counter to a preset
count at step 120. In the embodiment shown in FIG. 2, the preset
count is programmed by a user with the control panel 34. As noted
above, the user may set the preset count as a volume of lubricant
to be dispensed, a weight of lubricant to be dispensed, or a number
of pump strokes to be performed by the pump assembly 22. If the
pump cycle counter is greater than or equal to the preset count,
the lubricant measurement system stops the motor 18 at step 124 to
stop dispensing lubricant from the grease gun 10. If the pump cycle
counter is not greater than or equal to the preset count (i.e., if
the pump cycle counter is less than the preset count), the
lubricant measurement system continues to monitor the motor current
at step 116 until the Hall sensor is triggered again at step
104.
[0025] In some embodiments, the grease gun 10 may include means to
compensate for cylinder blow past lubricant by simultaneously
measuring the number of pump strokes and an output pressure of the
lubricant. The output pressure may be measured directly or may be
inferred from the motor current measurement. If the measured output
pressure is greater than a predetermined threshold value, the
grease gun 10 may provide an indication to the user and/or shutoff
power to the motor 18. Monitoring the output pressure may also help
prevent damage to gears of the motor 18 or the pump assembly 22 and
to the output hose 30 if the hose 30 becomes blocked.
[0026] In some embodiments, the grease gun 10 may include means to
remotely actuate the gun 10 from either an end of a hose proximate
a location being lubricated or from a tool handle. The means may
include a remote trigger having a light. The means may also include
a small plug, a small plug inside a shutter, or another optical
part positioned on the grease gun 10. The plug could be attached to
the grease gun 10 after the output hose 30 is connected to the gun
10.
[0027] FIGS. 4 and 5 illustrate another embodiment of an
electrically-powered grease gun 110. Similar to the grease gun 10
discussed above, the illustrated grease gun 110 includes a housing
114, a motor 118 supported by and positioned within the housing
114, a pump assembly 122 coupled to and driven by the motor 118,
and a chamber 126 supported by the housing 115 in fluid
communication with the pump assembly 122. The housing 114 includes
a battery connection portion 130 configured to support a battery
pack and connect the battery pack to the motor 118. Although not
shown, the grease gun 110 may also include an output hose having an
outlet in fluid communication with the chamber 126.
[0028] The grease gun 110 further includes a lubricant measurement
system that determines the amount of lubricant (e.g., grease) being
pumped and dispensed from the grease gun 110 during operation. The
lubricant measurement system functions in a similar manner to the
lubricant measurement system described above with reference to
FIGS. 2 and 3, but includes a manual actuator 134 rather than the
control panel 34 to control the system. In the illustrated
embodiment, the manual actuator 134 includes a rotatable dial. In
other embodiments, the manual actuator 134 may include a knob, a
switch, a lever, or any other suitable actuator that can be
manipulated by a user.
[0029] As shown in FIG. 4, the illustrated dial 134 is supported by
the housing 114 near a handle portion 138 and a trigger 142 of the
grease gun 110. The dial 134 is positioned mostly within the
housing 114, but a relatively small portion of the dial 134 extends
outwardly through an opening in the housing 114 such that the dial
134 is accessible by a user. A series of values that represent
numbers of pump strokes to be performed is listed on the outer
surface of the dial 134. An indicator 146 is formed on the housing
114 adjacent the portion of the dial 134 that extends through the
housing 114. The indicator 146 identifies for a user the current
setting of the dial 134.
[0030] As shown in FIGS. 5-7, the dial 134 is coupled to a circuit
board 150, which includes the processor and the memory of the
lubricant measurement system. The circuit board 150 is mounted
within a forward end portion of the housing 114, and the dial 134
is rotatably mounted on a boss 154 extending from the circuit
board. By rotating the dial 134, a user can set the number of pump
strokes that will be performed by the grease gun 110 when the
trigger 142 is actuated. For example, the dial 134 may be set such
that the grease gun 110 performs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15,
20, 25, or 50 pump strokes when the trigger 142 is actuated. The
number of pump strokes to be performed is identified by the
corresponding values on the dial 134. When the set number of pump
strokes is reached, the motor 118 automatically shuts down so that
the pump assembly 122 does not continue to operate and dispense
lubricant from the grease gun 110. In other embodiments, additional
or alternative numbers of pump strokes may be available using the
dial 134. In the illustrated embodiment, the dial 134 also includes
an ON setting. In this setting, the motor 118 and the pump assembly
122 operate continuously until the trigger 142 is released.
[0031] Although the invention has been described in detail with
reference to certain preferred embodiments, variations and
modifications exist within the scope and spirit of one or more
independent aspects of the invention as described. For example,
although the fluid measurement system has been described with
reference to a grease gun, the fluid measurement system may also be
employed with other types of motorized fluid dispensers, such as
caulk guns, soap or cleaner dispensers, paint sprayers or
dispensers, or the like. Furthermore, these dispensers may be used
to dispense other types of liquids (e.g., caulk, soap, paint, etc.)
instead of a lubricant.
[0032] One or more independent features and advantages of the
invention may be set forth in the following claims:
* * * * *